This is beyond suspicious and an insult to her. He is trying to use a person and still keep them at arm's length. I have never heard of such a strange setup. He is "sharing" as you say but he can't trust her with basic information like a phone number. What it sounds like she has is a relationship that is a huge secret. Intimacy doesn't survive in secret. I don't know how to say this comment nicely but he is using her for certain benefits while maintaining some other lifestyle in public. She is in a relationship but he isn't. When you can't acknowledge someone then they do not mean enough to do so. She needs to run. Instead of wasting her time find someone who is proud to be together. She needs to wake up. This guy is using her and when she puts her foot down he will be gone.
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